1. Field of the Invention
This invention relates to the reduction of carbon oxides. In one aspect, the invention relates to the reduction of carbon monoxide and/or carbon dioxide with hydrogen sulfide while in another aspect, the invention relates to the upgrading of these carbon oxides to organic compounds. In yet another aspect, the invention relates to various thermochemical cycles useful for this upgrading and which employ carbonyl sulfide as a reaction intermediate.
2. Description of the Prior Art
As petroleum and natural gas reserves are continually depleted, the incentive to find alternate sources of fuels and chemicals continually increases. Many studies have been made on the hydrogenation of carbon monoxide and/or carbon dioxide to organic compounds, e.g. alkanes, alcohols, alkenes, etc., but a common drawback to these studies is the requirement for large quantities of molecular hydrogen. This requirement adds considerable expense to the proposed processes and when alkanes, alkenes and higher alcohols are the desired products, part of the valuable hydrogen is wasted in the form of by-product water. As a consequence, there continues a search for alternative ways of upgrading the carbon oxides by hydrogenation to various organic compounds.